JRC JMR-92 Series Field Service Manual page 135

J4302: Termination resistor settings for GYRO-RX / AIS-RX
Termination resistor ON / OFF setting for GYRO-RX and AIS-RX can be changed by TB5 and
TB6 on the CCU I/F circuit CMH-2406.
If the Display Unit has the Serial number of "LC58298" or less, this setting is not
available.
1. Confirm that the Serial number of the Display unit is greater than "LC58298".
- Stand alone type
- Desktop /
Flush mount type :
2. Disassemble the CCU. Divide it into Upper base and Bottom base. For further information,
see "Field Service Manual 4.3.3.2 Replacing with the CCU Repair Kit NZC-1590".
3. Set TB5 and TB6 as follows. They are on the CCU I/F circuit mounted on the Upper base.
: The Serial number has been affixed to the front cover of
the Display Unit mount kit.
The Serial number has been affixed to the top side of
NDC-1590 :CCU.
2-77 Chapter 2 System Configuration